Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 547
Filtrar
1.
Toxicol Lett ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38768836

RESUMO

Desensitization of nicotinic acetylcholine receptors (nAChRs) can be induced by overstimulation with acetylcholine (ACh) caused by an insufficient degradation of ACh after poisoning with organophosphorus compounds (OPCs). Currently, there is no generally applicable treatment for OPC poisoning that directly targets the desensitized nAChR. The bispyridinium compound MB327, an allosteric modulator of nAChR, has been shown to act as a resensitizer of nAChRs, indicating that drugs binding directly to nAChRs can have beneficial effects after OPC poisoning. However, MB327 also acts as an inhibitor of nAChRs at higher concentrations and can thus not be used for OPC poisoning treatment. Consequently, novel, more potent resensitizers are required. To successfully design novel ligands, the knowledge of the binding site is of utmost importance. Recently, we performed in silico studies to identify a new potential binding site of MB327, MB327-PAM-1, for which a more affine ligand, UNC0646, has been described. In this work, we performed ligand-based screening approaches to identify novel analogs of UNC0646 to help further understand the structure-affinity relationship of this compound class. Furthermore, we used structure-based screenings and identified compounds representing four new chemotypes binding to MB327-PAM-1. One of these compounds, cycloguanil, is the active metabolite of the antimalaria drug proguanil and shows a higher affinity towards MB327-PAM-1 than MB327. Furthermore, cycloguanil can reestablish the muscle force in soman-inhibited rat muscles. These results can act as a starting point to develop more potent resensitizers of nAChR and to close the gap in the treatment after OPC poisoning.

2.
Toxicol Lett ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38759939

RESUMO

Poisoning with organophosphorus compounds, which can lead to a cholinergic crisis due to the inhibition of acetylcholinesterase and the subsequent accumulation of acetylcholine (ACh) in the synaptic cleft, is a serious problem for which treatment options are currently insufficient. Our approach to broadening the therapeutic spectrum is to use agents that interact directly with desensitized nicotinic acetylcholine receptors (nAChRs) in order to induce functional recovery after ACh overstimulation. Although MB327, one of the most prominent compounds investigated in this context, has already shown positive properties in terms of muscle force recovery, this compound is not suitable for use as a therapeutic agent due to its insufficient potency. By means of in silico studies based on our recently presented allosteric binding pocket at the nAChR, i.e. the MB327-PAM-1 binding site, three promising MB327 analogs with a 4-aminopyridinium ion partial structure (PTM0056, PTM0062 and PTM0063) were identified. In this study, we present the synthesis and biological evaluation of a series of new analogs of the aforementioned compounds with a 4-aminopyridinium ion partial structure (PTM0064-PTM0072), as well as hydroxy-substituted analogs of MB327 (PTMD90-0012 and PTMD90-0015) designed to substitute entropically unfavorable water clusters identified during molecular dynamics simulations. The compounds were characterized in terms of their binding affinity towards the aforementioned binding site by applying the UNC0642 MS Binding Assays and in terms of their muscle force reactivation in rat diaphragm myography. More potent compounds were identified compared to MB327, as some of them showed a higher affinity towards MB327-PAM-1 and also a higher recovery of neuromuscular transmission at lower compound concentrations. To improve the treatment of organophosphate poisoning, direct targeting of nAChRs with appropriate compounds is a key step, and this study is an important contribution to this research.

3.
PNAS Nexus ; 3(4): pgae104, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38562583

RESUMO

Schistosomiasis, a widespread neglected tropical disease, presents a complex and multifaceted clinical-pathological profile. Using hamsters as final hosts, we dissected molecular events following Schistosoma mansoni infection in the liver-the organ most severely affected in schistosomiasis patients. Employing tandem mass tag-based proteomics, we studied alterations in the liver proteins in response to various infection modes and genders. We examined livers from female and male hamsters that were: noninfected (control), infected with either unisexual S. mansoni cercariae (single-sex) or both sexes (bisex). The infection induced up-regulation of proteins associated with immune response, cytoskeletal reorganization, and apoptotic signaling. Notably, S. mansoni egg deposition led to the down-regulation of liver factors linked to energy supply and metabolic processes. Gender-specific responses were observed, with male hamsters showing higher susceptibility, supported by more differentially expressed proteins than found in females. Of note, metallothionein-2 and S100a6 proteins exhibited substantial up-regulation in livers of both genders, suggesting their pivotal roles in the liver's injury response. Immunohistochemistry and real-time-qPCR confirmed strong up-regulation of metallothionein-2 expression in the cytoplasm and nucleus upon the infection. Similar findings were seen for S100a6, which localized around granulomas and portal tracts. We also observed perturbations in metabolic pathways, including down-regulation of enzymes involved in xenobiotic biotransformation, cellular energy metabolism, and lipid modulation. Furthermore, lipidomic analyses through liquid chromatography-tandem mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry imaging identified extensive alterations, notably in cardiolipin and triacylglycerols, suggesting specific roles of lipids during pathogenesis. These findings provide unprecedented insights into the hepatic response to S. mansoni infection, shedding light on the complexity of liver pathology in this disease.

4.
Viruses ; 16(4)2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675828

RESUMO

The innate immune response to viruses is formed in part by interferon (IFN)-induced restriction factors, including ISG15, p21, and SAMHD1. IFN production can be blocked by the ISG15-specific protease USP18. HIV-1 has evolved to circumvent host immune surveillance. This mechanism might involve USP18. In our recent studies, we demonstrate that HIV-1 infection induces USP18, which dramatically enhances HIV-1 replication by abrogating the antiviral function of p21. USP18 downregulates p21 by accumulating misfolded dominant negative p53, which inactivates wild-type p53 transactivation, leading to the upregulation of key enzymes involved in de novo dNTP biosynthesis pathways and inactivated SAMHD1. Despite the USP18-mediated increase in HIV-1 DNA in infected cells, it is intriguing to note that the cGAS-STING-mediated sensing of the viral DNA is abrogated. Indeed, the expression of USP18 or knockout of ISG15 inhibits the sensing of HIV-1. We demonstrate that STING is ISGylated at residues K224, K236, K289, K347, K338, and K370. The inhibition of STING K289-linked ISGylation suppresses its oligomerization and IFN induction. We propose that human USP18 is a novel factor that potentially contributes in multiple ways to HIV-1 replication.


Assuntos
HIV-1 , Ubiquitina Tiolesterase , Ubiquitinas , Replicação Viral , Ubiquitina Tiolesterase/metabolismo , Ubiquitina Tiolesterase/genética , Humanos , HIV-1/fisiologia , HIV-1/genética , Ubiquitinas/metabolismo , Ubiquitinas/genética , Citocinas/metabolismo , Citocinas/genética , Imunidade Inata , Infecções por HIV/virologia , Infecções por HIV/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Interações Hospedeiro-Patógeno , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/genética
5.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656556

RESUMO

Multimodal in situ experiments during slot-die coating of thin films pioneer the way to kinetic studies on thin-film formation. They establish a powerful tool to understand and optimize the formation and properties of thin-film devices, e.g., solar cells, sensors, or LED films. Thin-film research benefits from time-resolved grazing-incidence wide- and small-angle x-ray scattering (GIWAXS/GISAXS) with a sub-second resolution to reveal the evolution of crystal structure, texture, and morphology during the deposition process. Simultaneously investigating optical properties by in situ photoluminescence measurements complements in-depth kinetic studies focusing on a comprehensive understanding of the triangular interdependency of processing, structure, and function for a roll-to-roll compatible, scalable thin-film deposition process. Here, we introduce a modular slot-die coater specially designed for in situ GIWAXS/GISAXS measurements and applicable to various ink systems. With a design for quick assembly, the slot-die coater permits the reproducible and comparable fabrication of thin films in the lab and at the synchrotron using the very same hardware components, as demonstrated in this work by experiments performed at Deutsches Elektronen-Synchrotron (DESY). Simultaneous to GIWAXS/GISAXS, photoluminescence measurements probe optoelectronic properties in situ during thin-film formation. An environmental chamber allows to control the atmosphere inside the coater. Modular construction and lightweight design make the coater mobile, easy to transport, quickly extendable, and adaptable to new beamline environments.

6.
Anal Chem ; 96(16): 6311-6320, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38594017

RESUMO

Schistosomiasis is a neglected tropical disease caused by worm parasites of the genus Schistosoma. Upon infection, parasite eggs can lodge inside of host organs like the liver. This leads to granuloma formation, which is the main cause of the pathology of schistosomiasis. To better understand the different levels of host-pathogen interaction and pathology, our study focused on the characterization of glycosphingolipids (GSLs). For this purpose, GSLs in livers of infected and noninfected hamsters were studied by combining high-spatial-resolution atmospheric-pressure scanning microprobe matrix-assisted laser desorption/ionization mass spectrometry imaging (AP-SMALDI MSI) with nanoscale hydrophilic interaction liquid chromatography tandem mass spectrometry (nano-HILIC MS/MS). Nano-HILIC MS/MS revealed 60 GSL species with a distinct saccharide and ceramide composition. AP-SMALDI MSI measurements were conducted in positive- and negative-ion mode for the visualization of neutral and acidic GSLs. Based on nano-HILIC MS/MS results, we discovered no downregulated but 50 significantly upregulated GSLs in liver samples of infected hamsters. AP-SMALDI MSI showed that 44 of these GSL species were associated with the granulomas in the liver tissue. Our findings suggest an important role of GSLs during granuloma formation.


Assuntos
Glicoesfingolipídeos , Fígado , Schistosoma mansoni , Esquistossomose mansoni , Animais , Glicoesfingolipídeos/metabolismo , Glicoesfingolipídeos/química , Fígado/metabolismo , Fígado/parasitologia , Cricetinae , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Mesocricetus , Cromatografia Líquida , Masculino
7.
BMC Vet Res ; 20(1): 136, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575983

RESUMO

BACKGROUND: Brachyspira (B.) pilosicoli is a zoonotic pathogen, able to infect different animal species such as pigs, poultry, and rodents, causing intestinal spirochetosis. An association of gastrointestinal clinical signs, such as diarrhea, with the isolation of B. pilosicoli from fecal samples or rectal swabs has not been proven in dogs. Other Brachyspira species commonly isolated from dogs, such as "B. canis" and "B. pulli", are considered commensals. This study investigated the occurrence of different Brachyspira species in rectal swabs and fecal samples in an independent canine cohort in central Germany. These included samples from shelter dogs, hunting dogs, and dogs presenting at regional small animal practices with various clinical signs. Data about the dogs, including potential risk factors for Brachyspira isolation, were obtained using a standardized questionnaire. The study also longitudinally investigated a colony of Beagle dogs for Brachyspira over 5 years. RESULTS: The rate of Brachyspira spp. isolation was 11% and included different Brachyspira species ("B. canis", "B. pulli", and B. pilosicoli). "B. canis" was detected in 18 dogs, whereas B. pilosicoli was only isolated from 1 dog in the independent cohort (not including the Beagle colony). Risk factors for shedding Brachyspira and "B. canis" were being less than 1 year of age and shelter origin. Gastrointestinal signs were not associated with the shedding of Brachyspira. B. pilosicoli and "B. canis" were isolated from several dogs of the same Beagle colony in 2017 and again in 2022, while Brachyspira was not isolated at multiple sampling time points in 2021. CONCLUSIONS: Shedding of B. pilosicoli in dogs appears to be uncommon in central Germany, suggesting a low risk of zoonotic transmission from dogs. Commensal status of "B. canis" and "B. pulli" is supported by the results of this study. Findings from the longitudinal investigation of the Beagle colony agree with an asymptomatic long-term colonization of dogs with "B. canis" and B. pilosicoli and suggest that introducing new animals in a pack can trigger an increased shedding of B. pilosicoli.


Assuntos
Brachyspira , Humanos , Animais , Cães , Suínos , Estudos Longitudinais , Aves Domésticas , Fatores de Risco , Alemanha/epidemiologia
8.
PLoS Biol ; 22(4): e3002597, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38684033

RESUMO

Intestinal epithelial cells (IECs) play pivotal roles in nutrient uptake and in the protection against gut microorganisms. However, certain enteric pathogens, such as Salmonella enterica serovar Typhimurium (S. Tm), can invade IECs by employing flagella and type III secretion systems (T3SSs) with cognate effector proteins and exploit IECs as a replicative niche. Detection of flagella or T3SS proteins by IECs results in rapid host cell responses, i.e., the activation of inflammasomes. Here, we introduce a single-cell manipulation technology based on fluidic force microscopy (FluidFM) that enables direct bacteria delivery into the cytosol of single IECs within a murine enteroid monolayer. This approach allows to specifically study pathogen-host cell interactions in the cytosol uncoupled from preceding events such as docking, initiation of uptake, or vacuole escape. Consistent with current understanding, we show using a live-cell inflammasome reporter that exposure of the IEC cytosol to S. Tm induces NAIP/NLRC4 inflammasomes via its known ligands flagellin and T3SS rod and needle. Injected S. Tm mutants devoid of these invasion-relevant ligands were able to grow in the cytosol of IECs despite the absence of T3SS functions, suggesting that, in the absence of NAIP/NLRC4 inflammasome activation and the ensuing cell death, no effector-mediated host cell manipulation is required to render the epithelial cytosol growth-permissive for S. Tm. Overall, the experimental system to introduce S. Tm into single enteroid cells enables investigations into the molecular basis governing host-pathogen interactions in the cytosol with high spatiotemporal resolution.


Assuntos
Proteínas de Ligação ao Cálcio , Citosol , Flagelina , Interações Hospedeiro-Patógeno , Inflamassomos , Salmonella typhimurium , Sistemas de Secreção Tipo III , Citosol/metabolismo , Citosol/microbiologia , Animais , Salmonella typhimurium/patogenicidade , Salmonella typhimurium/metabolismo , Sistemas de Secreção Tipo III/metabolismo , Inflamassomos/metabolismo , Camundongos , Flagelina/metabolismo , Proteína Inibidora de Apoptose Neuronal/metabolismo , Proteína Inibidora de Apoptose Neuronal/genética , Células Epiteliais/microbiologia , Células Epiteliais/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , Camundongos Endogâmicos C57BL , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas Adaptadoras de Sinalização CARD/genética , Análise de Célula Única/métodos , Infecções por Salmonella/microbiologia , Infecções por Salmonella/metabolismo , Infecções por Salmonella/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo
9.
Ann Transl Med ; 12(1): 14, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38304906

RESUMO

The ProtekDuo (LivaNova, London, UK) cannula is a dual-lumen device, typically inserted into the right internal jugular (IJ) vein through a percutaneous approach, with fluoroscopy or ultrasound guidance. When connected to a pump, such as the TandemHeart (LivaNova, London, UK) or CentriMag (Abbott, Pleasanton, CA, USA), it can function as a right ventricular (RV) mechanical circulatory support (MCS). When an oxygenator is also added [veno-pulmonary (V-P)], it can provide extracorporeal membrane oxygenation (ECMO) support. This review aims to provide a comprehensive overview of the device's physiology and clinical applications. In the setting of RV failure (RVF), the ProtekDuo cannula, with its outflow in the main pulmonary artery (PA), can bypass the failing RV, improving pulmonary flow, left atrial (LA) filling pressures, and left ventricular (LV) preload. This can also reduce ventricular interdependence and leftward shift of the interventricular septum that occurs in RVF. In this review, the key sections expand on the use of the ProtekDuo cannula in the management of critically ill patients, specifically, the use of ProtekDuo for RV myocardial infarction (MI) RVF, LV assist device (LVAD) implantation-associated RVF, RVF post-heart transplantation, temporary biventricular MCS as bridge to recovery (ECpella 2.0 or PROpella), biventricular support as bridge to recovery or decision, isolated LV failure, post lung transplantation (LT) care, and other miscellaneous clinical scenarios. ProtekDuo is an important tool in the armory of RVF management. The ProtekDuo system is expected to gain more popularity given its clear advantages such as groin-free approach allowing for mobility, easy percutaneous deployment, compatibility with various pumps and oxygenators, and the versatility to be integrated in numerous configurations. In an era of expanding MCS options, further research is needed to better understand the optimal tool for specific patient subsets.

11.
Diagnostics (Basel) ; 14(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38396392

RESUMO

PURPOSE: Evaluation of the effectiveness of CT-guided drainage (CTD) placement in managing symptomatic postoperative fluid collections in liver transplant patients. The assessment included technical success, clinical outcomes, and the occurrence of complications during the peri-interventional period. METHODS: Analysis spanned the years 2005 to 2020 and involved 91 drain placement sessions in 50 patients using percutaneous transabdominal or transhepatic access. Criteria for technical success (TS) included (a) achieving adequate drainage of the fluid collection and (b) the absence of peri-interventional complications necessitating minor or prolonged hospitalization. Clinical success (CS) was characterized by (a) a reduction or normalization of inflammatory blood parameters within 30 days after CTD placement and (b) the absence of a need for surgical revision within 60 days after the intervention. Inflammatory markers in terms of C-reactive protein (CRP), leukocyte count and interleukin-6, were evaluated. The dose length product (DLP) for various intervention steps was calculated. RESULTS: The TS rate was 93.4%. CS rates were 64.3% for CRP, 77.8% for leukocytes, and 54.5% for interleukin-6. Median time until successful decrease was 5.0 days for CRP and 3.0 days for leukocytes and interleukin-6. Surgical revision was not necessary in 94.0% of the cases. During the second half of the observation period, there was a trend (p = 0.328) towards a lower DLP for the entire intervention procedure (median: years 2013 to 2020: 623.0 mGy·cm vs. years 2005 to 2012: 811.5 mGy·cm). DLP for the CT fluoroscopy component was significantly (p = 0.001) lower in the later period (median: years 2013 to 2020: 31.0 mGy·cm vs. years 2005 to 2012: 80.5 mGy·cm). CONCLUSIONS: The TS rate of CT-guided drainage (CTD) placement was notably high. The CS rate ranged from fair to good. The reduction in radiation exposure over time can be attributed to advancements in CT technology and the growing expertise of interventional radiologists.

12.
Nat Microbiol ; 9(1): 136-149, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38172620

RESUMO

In healthy plants, the innate immune system contributes to maintenance of microbiota homoeostasis, while disease can be associated with microbiome perturbation or dysbiosis, and enrichment of opportunistic plant pathogens like Xanthomonas. It is currently unclear whether the microbiota change occurs independently of the opportunistic pathogens or is caused by the latter. Here we tested if protein export through the type-2 secretion system (T2SS) by Xanthomonas causes microbiome dysbiosis in Arabidopsis thaliana in immunocompromised plants. We found that Xanthomonas strains secrete a cocktail of plant cell wall-degrading enzymes that promote Xanthomonas growth during infection. Disease severity and leaf tissue degradation were increased in A. thaliana mutants lacking the NADPH oxidase RBOHD. Experiments with gnotobiotic plants, synthetic bacterial communities and wild-type or T2SS-mutant Xanthomonas revealed that virulence and leaf microbiome composition are controlled by the T2SS. Overall, a compromised immune system in plants can enrich opportunistic pathogens, which damage leaf tissues and ultimately cause microbiome dysbiosis by facilitating growth of specific commensal bacteria.


Assuntos
Microbiota , Sistemas de Secreção Tipo II , Xanthomonas , Xanthomonas/genética , Disbiose , Folhas de Planta
13.
Toxicol Lett ; 392: 94-106, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216073

RESUMO

Intoxications with organophosphorus compounds (OPCs) based chemical warfare agents and insecticides may result in a detrimental overstimulation of muscarinic and nicotinic acetylcholine receptors evolving into a cholinergic crisis leading to death due to respiratory failure. In the case of the nicotinic acetylcholine receptor (nAChR), overstimulation leads to a desensitization of the receptor, which cannot be pharmacologically treated so far. Still, compounds interacting with the MB327 binding site of the nAChR like the bispyridinium salt MB327 have been found to re-establish the functional activity of the desensitized receptor. Only recently, a series of quinazoline derivatives with UNC0642 as one of the most prominent representatives has been identified to address the MB327 binding site of the nAChR, as well. In this study, UNC0642 has been utilized as a reporter ligand to establish new Binding Assays for this target. These assays follow the concept of MS Binding Assays for which by assessing the amount of bound reporter ligand by mass spectrometry no radiolabeled material is required. According to the results of the performed MS Binding Assays comprising saturation and competition experiments it can be concluded, that UNC0642 used as a reporter ligand addresses the MB327 binding site of the Torpedo-nAChR. This is further supported by the outcome of ex vivo studies carried out with poisoned rat diaphragm muscles as well as by in silico studies predicting the binding mode of UNC0646, an analog of UNC0642 with the highest binding affinity, in the recently proposed binding site of MB327 (MB327-PAM-1). With UNC0642 addressing the MB327 binding site of the Torpedo-nAChR, this and related quinazoline derivatives represent a promising starting point for the development of novel ligands of the nAChR as antidotes for the treatment of intoxications with organophosphorus compounds. Further, the new MS Binding Assays are a potent alternative to established assays and of particular value, as they do not require the use of radiolabeled material and are based on a commercially available compound as reporter ligand, UNC0642, exhibiting one of the highest binding affinities for the MB327 binding site known so far.


Assuntos
Compostos de Piridínio , Receptores Nicotínicos , Ratos , Animais , Receptores Nicotínicos/metabolismo , Ligantes , Relação Estrutura-Atividade , Sítios de Ligação , Quinazolinas , Compostos Organofosforados , Torpedo/metabolismo
14.
Schmerz ; 2024 Jan 02.
Artigo em Alemão | MEDLINE | ID: mdl-38165491

RESUMO

BACKGROUND: Living wills/advance directives (AD) are an important tool for specifying patient wishes regarding medical care in the case of future inability to consent. Since 2009, German legislation defines framework conditions for the creation and validity of such directives in § 1901a BGB. METHODS: An extensive literature search in an international and a German-language database was conducted to identify, analyze, and evaluate scientific articles on opportunities, risks, and problems in the creation and implementation of living wills. RESULTS: Between 10 and 40% of patients have an AD. Among the stipulations in the AD, the demand for sufficient pain therapy is very important. However, numerous problems in the preparation and implementation of ADs reduce their value in everyday clinical practice. In particular, unclear conditions of validity, unspecific instructions for action, and lack of availability of the directives prevent practitioners from determining the patient's will. Other fundamental problems include frequent patient ambivalence and clinical ethical dissent. In addition, the framework condition of unlimited coverage set by the law carries the risk that changes of opinion in the course of life or disease are not taken into account. CONCLUSION: Preparing an AD requires a high level of information, consultation, and time, as well as regular review or adjustment of its content. These factors are often not considered, thus complicating implementation and reducing the value of living wills. Possible solutions to these problems or alternative concepts for different patient settings are discussed in this review.

18.
Int J Legal Med ; 138(1): 289-293, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36808299

RESUMO

We report the case of a woman in her thirties who suffered an esophageal rupture while participating in extreme sadomasochistic practices. After herself seeking help in a hospital for complaints alleged to be from a fall, she was initially diagnosed with several broken ribs and a pneumothorax. The cause of the pneumothorax was later discovered to be an esophageal rupture. When confronted with this atypical injury for a fall, the woman admitted to have accidentally swallowed an inflatable gag, which her partner had afterwards inflated. In addition to the esophageal rupture, the patient also had numerous other externally visible injuries of various ages, reportedly also from sadomasochistic acts. Although an in-depth police investigation was conducted and a "slave contract" was found, the woman's consent to the extreme sexual practices performed by her life partner could not be substantiated conclusively. The man was convicted for intentional infliction of serious as well as dangerous bodily injury and sentenced to a long term in prison.


Assuntos
Esôfago , Pneumotórax , Delitos Sexuais , Feminino , Humanos , Esôfago/lesões
19.
Cell Mol Gastroenterol Hepatol ; 17(1): 107-117, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37696392

RESUMO

BACKGROUND & AIMS: Schistosomiasis is one of the most prominent parasite-induced infectious diseases, affecting more than 250 million people. Schistosoma mansoni causes metabolic exhaustion and a strong redox imbalance in the liver, causing parenchymal damage, and may predispose for cancer. We investigated whether oxidative stress provokes hepatocellular proliferation upon S. mansoni infection. METHODS: The cell cycle, replication stress response, and proliferation were analyzed on transcriptional and protein levels in the livers of S. mansoni-infected hamsters and by mechanistic gain- and loss-of-function experiments in human hepatoma cells. Major results were validated in human biopsy specimens of S. mansoni-infected patients. RESULTS: S. mansoni infection induced licensing factors of DNA replication and cell-cycle checkpoint cyclins in parallel with a DNA damage response in hamster hepatocytes. Moreover, even unisexual infection without egg effects, as a reflection of a chronic inflammatory process, resulted in a moderate activation of several cell-cycle markers. S. mansoni soluble egg antigens induced proliferation of human hepatoma cells that could be abolished by reduced glutathione. CONCLUSIONS: Our data suggest that hepatocellular proliferation is triggered by S. mansoni egg-induced oxidative stress.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Esquistossomose mansoni , Cricetinae , Animais , Humanos , Schistosoma mansoni/fisiologia , Esquistossomose mansoni/metabolismo , Estresse Oxidativo , Proliferação de Células
20.
Faraday Discuss ; 249(0): 69-83, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-37794776

RESUMO

Hydrophobic molecules are by definition difficult to hydrate. Previous studies in the area of hydrophobic hydration have therefore often relied on using amphiphilic molecules where the hydrophilic part of a molecule enabled the solubility in liquid water. Here, we show that the hydrophobic adamantane (C10H16) molecule can be fully hydrated through vapour codeposition with water onto a cryogenic substrate at 80 K resulting in the matrix isolation of adamantane in amorphous ice. Using neutron diffraction in combination with the isotopic substitution method and the empirical potential structure refinement technique, we find that the first hydration shell of adamantane is well structured consisting of a hydrogen-bonded cage of 28 water molecules that is also found in cubic structure II clathrate hydrates. The four hexagonal faces of the 51264 cage are situated above the four methine (CH) groups of adamantane whereas the methylene (CH2) groups are positioned below the edges of two adjoining pentagonal faces. The oxygen atoms of the 28 water molecules can be categorised on the basis of symmetry equivalences as twelve A, twelve B and four C oxygens. The water molecules of the first hydration shell display orientations consistent with those expected for a clathrate-hydrate-type cage, but also unfavourable ones with respect to the hydrogen bonding between the water molecules. Annealing the samples at 140 K, which is just below the crystallisation temperature of the matrix, removes the unfavourable orientations and leads to a slight increase in the structural order of the first hydration shell. The very closest water molecules display a tendency for their dipole moments to point towards the adamantane which is attributed to steric effects. Other than this, no significant polarisation effects are observed which is consistent with weak interactions between adamantane and the amorphous ice matrix. FT-IR spectroscopy shows that the incorporation of adamantane into amorphous ice leads to a weakening of the hydrogen bonds. In summary, the matrix-isolation of the highly symmetric adamantane in amorphous ice provides an interesting test case for hydrophobic hydration. Studying the structure and spectroscopic properties of water at the interface with hydrophobic hydrocarbons is also relevant for astrophysical environments, such as comets or the interstellar medium, where amorphous ice and hydrocarbons have been shown to coexist in large quantities.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...